Hurricane Franklin is making landfall on the East Coast of Mexico Wednesday night/early Thursday morning (~midnight CDT Thursday) with maximum sustained winds of 85 mph with gusts likely over 100 mph. Besides damaging wind gusts, very heavy rain – up to a foot or more – will be possible in the mountainous terrain once the system moves inland and weakens during the day Thursday. Life threatening flash flooding and mudslides will be the greatest threats to any populated mountain areas (storm surge will be the hazard for coastal areas in the hurricane warning area tonight).
NOAA Raises North Atlantic Tropical Activity Forecast
The National Oceanographic and Atmospheric Administration raised its confidence today that the North Atlantic Basin would have an “very active” season. They called for 14-19 named storms, 5-9 hurricanes, 2-5 major hurricanes. A normal season averages 11 named storms, 6 hurricanes, 2 major hurricanes.
The reasoning for this activity forecast include 1) No El-Nino in the Eastern Pacific which would otherwise produce unfavorable vertical wind shear and cooler sea surface temperatures in the North Atlantic 2) Above normal sea surface temperatures across the Caribbean, Gulf of Mexico and Main Development Region (open tropical Atlantic) 3) The continuation of the Atlantic Multidecadal Oscillation favoring above normal oceanic heat content.
So far, we are at 6 named storms, 1 hurricane, 0 major hurricanes (assuming no surprise intensification of Franklin prior to landfall).
The Northern US Great Plains into the southern Canadian Prairies are suffering from a growing drought problem. The National Drought Mitigation Center at the University of Nebraska-Lincoln released their weekly drought monitor which updates on the drought situation for the entire country (every Thursday based on Tuesday data). Drought overall across the United States has begun to grow in coverage and intensity. This can happen just from the local abnormalities in a summer season. However, a persistent pattern of dryness has developed over the Northern Plains beginning in May where significantly below normal rainfall has caused soils and hydrologic sources to begin to dry out.
Comparison of drought conditions currently (July 18, 2017) and 3 months earlier. Mostly areas of “abnormally dry” conditions over KS, CO and very spotty over over other areas.
Comparison of drought conditions currently (July 18, 2017) and 3 months earlier. Mostly areas of “abnormally dry” conditions over KS, CO and very spotty over over other areas. Now dramatically worse in mid-July over the Dakotas and northern Nebraska. (Maps by NDMC).
I took a look at some meteorological stations for their recent climate records. Rapid City, SD (currently in the moderate drought zone) is running 3.37 inches below normal in rainfall for the May 1st-July 21st period. In Bismarck, ND (in severe drought) is even worse at 4.01 inches below normal for the same period. May dryness hit the region hard with a major monthly deficit then it simply continued into the summer. At least moderate drought covers ~28% of the above region (ND, SD, NE, KS, WY, CO). Moderate conditions can result in some damage to crops and reduction in stream/river flows and lowering of lake levels. Extreme – which now exists in spots of southwest ND – can mean widespread and devastating agricultural losses and severe reductions in hydrologic sources.
Obviously, “equal chances”- which is based on the expected evolution of various climate patterns – means that there could very well be above average rainfall, which the region really needs at this point to get out of the growing deficit. However, if it ends up being near-normal, they may continue to simply lag behind with similarly bad impacts. Below normal means a worsening and spreading of drought conditions and further difficulty removing the existing drought (anyone remember the difficulty California had in getting out of drought?). Folks in these areas should be prepared for any further water restrictions and do what they can now to conserve in case the dryness lasts longer than expected.
Elsewhere, dryness and moderate drought has begun to spread into parts of the Intermountain West and Four Corners.
Quick update from the Eastern Pacific tropics…new tropical depression! Tropical Depression Ten-E is rolling around between Tropical Storm Greg and TD Nine-E. It’s expected to become a tropical storm in the coming days as it generally moves westward over the open ocean. So there are now 4 existing cyclones in the tropical North Pacific east of 180 longitude. Although Fernanda is dying quickly over cooler waters and dry mid-level air and will likely dissipate by tomorrow.
Welcome to the inaugural post of Weather and Climate News! There’s much going on this week, but the most significant has been the intense heat over the center of the country as very strong high pressure system has entrenched itself over the region. This, in combination with dew points of 70-80 degrees, was allowed for heat indices of 105-115 degrees F to steam much of Plains, Midwest and Deep South. This, while periodic areas of thunderstorms, some severe, form around the periphery of the clockwise high pressure system. Heat advisories and excessive heat warnings are in effect today as a result of the potential health hazards of the heat. Be safe and drink lots of water! Particularly in areas with heat or heat indices in the triple digits when you may be outdoors for long periods.
The intense heat will relax a bit over the Central Plains this weekend as a result of a “cold” (more like cool?) front with temperatures closer to seasonal norms.
The Central and Eastern Pacific is quite active with the tropical cyclone activity! Eastern Pacific activity can of course impact Mexico, but (more typically later in the season) enhance the Southeast US monsoon with either additional atmospheric moisture for afternoon thunderstorms or (rarely) move ashore Mexico or into the United States as an organized tropical depression or weak tropical storm. Today, however, neither country has any issues from any of these systems today. Three to be exact, with a four likely imminent. All of these cyclones…Tropical Storm Fernanda (born in the East, but now in the Central Pacific west of 140W longitude), Tropical Storm Greg, and Tropical Depression Nine-E are all moving away from major land masses and populated areas.
The Eastern Pacific Basin (defined as 140W east to the continents and north of the equator) is running ahead of schedule in terms named storms to date (7), hurricanes (3) and major hurricanes…defined as Category 3 or higher strength (2). Fernanda was at one point the most intense hurricane of the season in the Eastern Pacific with maximum winds of 145 mph on July 14-15.
It’s now a shell of its former self and while it’s heading in the general direction of the State of Hawaii, it should continue to weaken dramatically as it encounters drier mid-level air and cooler waters. High surf and hazardous rip currents are the biggest threats to anyone doing recreational activity around the Big Island the next couple of days as the dying system moves to the north.